A remarkable finding incidental to the surgical management of Pseudomonas sclerokeratitis has led to the discovery that it is possible to transplant functional trabecular meshwork in humans. A 15mm corneoscleral graft was performed to save an eye with a ring abscess. All host trabecular tissue was excised. Donor trabecular meshwork can be seen on gonioscopy, and intraocular pressure has remained between 10 and 20mm Hg for over 3 years with corrected vision of 20/25. Allograft rejection of the corneoscleral graft had no effect on intraocular pressure. During two subsequent procedures, a central optical keratoplasty and cataract extraction with lens implantation, no fistula or cyclodialysis cleft could be identified. To pursue the possibility that functional trabecular meshwork could be transplanted, a variation of this procedure was performed in two Cynomolgus monkeys. After three months, perfusion of the anterior chamber demonstrated aqueous outflow through the venous system, not into the subconjunctival space and histopathology demonstrated the absence of cyclodialysis cleft or fistula. Subsequently, an annular trabecular meshwork transplant was also performed in a patient with a blind eye and severe glaucoma. Intraocular pressure fell from 70 mm Hg to normal where it has remained for over 4 months. At three months it was possible to reflux blood into donor Schlemm's canal, indicating the reanastomosis of donor aqueous veins with the host venous system. The purpose of this study is to develop a practical surgical procedure for the transplantation of functional trabecular meshwork and to determine the essential surgical parameters for the use of this procedure as a treatment for experimental glaucoma. In Cynomolgus monkeys alloplastic trabecular meshwork will be transplanted over an area of 160 degrees. Half of the monkeys will be studied post-operatively by perfusion studies to determine if reanastomosis of aqueous veins occurs. The remainder will be pretreated with argon laser applications to trabecular meshwork to induce glaucoma. All animals will be followed for eight months to determine if the trabecular meshwork graft remains functional and controls intraocular pressure. Eyes will be examined histologically at the end of one year to document whether fistulae or dialyses might have provided an alternative pathway for aqueous outflow. The success of this pilot study would establish a new system for basic research on the fundamental relationship of the trabecular meshwork and glaucoma and would support an entirely new mode of surgical therapy for glaucoma.